A measuring device having such a housing is known, for example, from DE 10 2005 060 961 A1. The measuring device, also referred to as a measuring lance, principally comprises a tube in which the sensor lines and cooling air can be guided. The sensor lines and the coolant are introduced, or fed in, at one end of the tube. When the measuring lance is used in a gas turbine for radial gap detection, this end of the tube is arranged outside the housing of the gas turbine. The sensor is fastened on the other end of the tube. In order to protect the sensor from overheating, it is flanked by coaxial cooling air bores through which the cooling air flowing in the tube can emerge.
It is found disadvantageous that the sensor and its housing are relatively large and therefore have an increased cooling air requirement so that they can be used reliably. Another disadvantage is that the known measuring device is furthermore configured only for a single sensor.